Potato harvester



P 1953 c. v. EDWARDS 2,633,685

POTATO HARVESTER Filed July 29, 1946 6 Sheets-Sheet l INVENTOR. CURTISll EDWARDS A T TOR/VEV April 1953 c. v. EDWARDS 2,633,685

POTATO HARVESTER Filed July 29, 1946 6 Sheets-Sheet 2 IN VEN TOR. CURTISl. EDWARDS ATTORNEY April 1953 I c. v. EDWARDS 2,633,685

POTATO HARVESTER INVENTOR. CUATLS- l. EOWARD$ April 7, 1953 c. v.EDWARDS POTATO HARVESTER Filed July 29, 1946 6 Sheets$heet 4 IVER CUR77$ 1/ EDWARDS ATTORNEY April 7, 1953 c. v. EDWARDS 2,633,685

' POTATO HARVESTER 6 Sheets-Sheet Filed July 29, 1946 a9 as a7 70 a as I---3la INVENTOR.

30 7s 25 82 CURTIS u EDWARDS BY Z ATTORNEY April 7, 1953 c. v. EDWARDS2,633,685

' POTATO HARVESTER Filed July 29, 1946 6 Sheets-Sheet 6 IN V EN TOR. CUR77$ M E DWARDS A 7' TORNE Y Patented Apr. 7, 1953 POTATO HARYESTERCurtis V."Edwards, Yakima, Wash., assignor, by mesne assignments, toDeere & Company, Moline, Ill., a corporation of Illinois ApplicationJuly 29, 1946,'Serial No. 687,033

6 Claims.

This 'invention'relates to improvements in potato'harvesters and relatesin particular to" a potato harvester adapted to be moved through thefield which is ready for harvesting, which will dig up the potatoes andthe vines and sepa- -rate the vines from the potatoes, after which thepotatoes are elevated to a conveyor belt leading to holders for sacksinto whichthe'potatoes are delivered.

object of the invention is to provide in a harvester of this character adigging mechanism 'having'a novel 'depth control capable of readyadjustment by an operator who stands on a platform above the front endof the digging mechanism, to meet the varying conditions which'areencountered, and in addition to the adjusting 'mechanism having ahydraulic control which is likewise operated from the platform. i Amongthe conditions met in the use of the harvester are the different typesof soil, the variations in contour or levelness, and also the heightabove the furrowbottoms' of the hills from which the potato'es are to beharvested.

. object of the invention is to provide in a depth control mechanism alinkage arrangement whereby ground-engaging wheels are supported byindependent arms ahead of the digger bits .or prongs, there being meanswhereby the wheels and the front end of the digging mechanism have,diflerent rates of vertical travel, asthe result of the operation ofthe interconnecting linkage mechanism. The purpose of this difference.in vertical movement of the depth controlling wheels .of the digger bitsis to compensatefor the difference in height resulting'from the droppingof thewheels into holes or the, traveling ofthe wheels over humps In theoperation of the device, the manual adjustment may be employed to,changethe horizontal planes in which the depth control wheels and thedigger bitsoperate, but

this adjustment is accomplished without affecting the relativedifierence in vertical movement of the wheels and'the digger bits;

- A further object of the invention is to provide have intermediatepoints thereof connected-to the frame of the digger mechanism sothat-vertical movement of the wheels, as aresult ofdropping into theholesor riding over humps, transmits to the digger mechanisma verticalswinging movement which is different than the vertical swinging movementof the levers.

A further object of the invention is to provide a simplified andimproved chain belt which ex" tends over suitable guide rollers 01'sprockets from the lower end of the digging mechanism to an improvedvine-removing device for separating the vines from the potatoes so thatthey may drop onto a transverse conveyor of reticulated form to anelevator which delivers the potatoes to a novel and effective form ofcleaning mechanism. This cleaning'mechanism in turn delivers thepotatoes to a'horizontal conveyor or sorting belt which carries thepotatoes to the rear of the harvester and ultimately delivers thepotatoes into sacks. Platforms are provided on the vehicle on whichworkers stand, whose duties include sorting from the potatoes, rocks,clods,

.rate of travel of thepotatoes so that the fast movement of the vinesproduced by the v.vineremoving device results in the pulling of thevines from the potatoes, a. .7

A further object of the invention isto provide avine-removing deviceconsisting of revolving members having projections in the form of re-.silient fingers or spikes placed relatively close together and beingadapted to engage the vines as the vines and the potatoes passrearwardly from the rear end of the chain belt conveyor.

A further object is to provide a vine-removing device wherein theprojecting fingers are made of rubber and wherein the upper rotarymember of the vine-removing device is set forwardly of the lower rotary"part of the vineremoving device, the result being that the upper rotarymember tends to throw the potatoes downwardly so that none of them willstrike the upper portion of the lower rotary part of the vineremovingdevice and thereby avoid the carrying of potatoes into the gap betweenthe upper and lower rotary members of the vine-removing device whereinthey would be crushed.

A further object of the invention is to provide roller;

in conjunction with the digger mechanism a vine draper which will engagethe vines from above and carry them rearwardly up and beyond the rearend of the inclined portion of the digger mechanism. A further object ofthe invention is to provide a means for disposing the vines on the chainbelt in such position that the vines extend rearwardly from the potatoesto which they are attached, the result being that the vines are broughtinto engagement with the vineremoving device before the thereto attachedpotatoes reach the rear end of the chain belt conveyor which extendsfrom the rear ends of the digging bits to the vine-removing device.

The means referred to in the preceding paragraph, in the presentembodiment of the invention, consists in the vine draper which providesrearwardly moving members in spaced relation to the link belt, thesemembers traveling rearward at a speed greater than the speed of thechain 'belt'so that the'vines are moved rearward at a speed greaterthanthat which the potatoes are moved, theeffect' being to dispose the vinesin positions rearwardly of the potatoes to which they are attached.

A-further object of the invention-is to provide a cleaning device toreceive the potatoes, such cleaning device comprising a set of rollersdisposedon substantially parallel, horizontal axes arranged so as tocorrespond to an'inclined plane, these rollers being rotated so that theexposed surfacesthereof-revolve in upward direction and have resilientprojections which engage the pota'toesas they move from the upper to thelower end of-the inclined cleaning device; A feature of-theirivention isthat these cleaning rollers projections on the cleaninglrolierseffectively carry off small vine portion's,' grass and'leaves,not'prev'iously separated from the potatoes.

A further object of the inventio'n'is'to provide a means forrotating'each upwardly succeeding roller of the potato-cleaningmechanism at a slightly greater speed than the preceding roller so thatvines will not be wrapped around the cleaningrollers; Since eachupwardly succeeding roller travels at slightly increased speed, thevines or trash are stripped off from the adjacent A further object ofthe invention is to provide a harvester having supporting wheelsadjustable as to width, and so arranged that the device may r be turnedonavery short radius. A further ob- J'ect of the invention is to providea steering connection between'the front and rear wheels whichcontributes to this short turning radius.

Further objects and advantages of the invention will-be brought out inthe following part of the specification.

Referring tothe drawings, which are for illustrative purposes only:

Fig. 1 is a side elevation, toreduced scale, of a. preferred formof myinvention;

Fig.2 is a planview corresponding to'Fig. 1; Fig. 3-is an enlargedelevational View of the front portion of the harvester shown in Fig. 1;

Fig. 4 is a fragmentary section taken as indi-:

' brought together at-theirforward ends.

Fig. 7 is an enlarged fragmentary section taken as indicated by the line'l'! of Fig. 3;

Fig. 8 is an enlarged elevation of the middle portion of the device;

Fig. 9 is a fragmentary sectional view taken as indicated by the line 99of Fig. 8;

Fig. 10 is a schematic plan view of the chassis, showing theadjustability'of the rear wheels and the steering connections.

Fig. 11 is an enlarged fragmentary sectional view of the portion of Fig.10 included in the circle I I;

Fig. 12 is an enlarged plan view of the portion of Fig. 10 included inthe circle !2;

Fig. 13 is a fragmentary view showing the depth control roller-employedunder some conditions; and

Fig. 14 is an enlarged fragmentary view of the mechanism included in thecircle of Fig. 8.

'The harvester includes a chassis It supported by front and rearwheelsHand 42. The chassis includes side frame members it which are AnengineIQ for operation of the mechanism of the harvester is mounted on the'forward portion'of the-"chassis it, there being a transmission gear boxextending rearwardly'from the engine and having a power output shaft 58'connected to a speed reducing gear $7. This speed reducing gear H,through a safety clutch i8, drivesa power input shaft it of an anglegeartt having a-transverse power output shaft H on which a sprocket 22is mounted soas to drive a chain 23 whereby power is carried to parts ofthe-mechanismto be hereinafter described.

Plates 24 extend downwardlyfrom :the side frame members 13 and from thelower ends of the plates 24 chassis frame members 25 are extendedrearwardly,'these chassis frame members being connected to the rear endsof the frame members l3 by posts "26. A digger frame 27 has itsrear endconnected to the plates 24 by a shaft 28 and from this shaft 28 thedigger frame 21 slopes downwardly and at its forward end has a seriesofforwardly projecting tines orbits 29 for engaging the ground and liftingthe potatoes, vines and entrained soil onto a flexible grid conveyor 30which'istrained over special, cone rollers 3! supported at the forwardend of, the digger frame 21 and-the upper run 3011 of which conveyorextends over a series of sprockets '32, 33 and 34 to sprockets 35disposed adjacent to thevines-removing mechanism .of the device. Thelower-run 30b of the flexible grid conveyor 30 passes back overidlersprockets 36 to the cone rollers 3|. The'sprockets 35 are mounted on atransverse shaft 3'! carrying large sprockets 38 .over which the drivechain 23 is trained, so that the sprockets 35 may be driven in adirection to pull the upper run-30a of the flexible grid conveyor 30upward from the rollers 3!.

A vine draper '39 is provided for draping the vines rearwardly from thepotatoes to which they are attached, so that when the upper rear end'ofthe travel of the upper run-30a of the flexible grid conveyor 30 isreached, the vines will arrive at the vine-removing device R ahead ofthe potatoes. This vine draper comprises a traveling chain or'belt 40arranged above the flexible grid conveyor 30 and has downwardlyprojecting rubber or rubber-coveredmembers 4! for engaging the vines anddragging them rearwardly. This rearward dragging or draping of the vinesis accomplished byrunning the belt 40 sprockets 431' The sprockets 42are carried atthe frontend of a vine draper frame 44 which has itsintermediate portion resting on adjustable supports 45 and has its rearend carried by-a stub bearing shaft 45. The rear sprockets 43 f the vinedraper are carried on a transverse shaft 41 having thereonlarger-sprockets 48 over which the lower portion 230. of the chain 23passes. whereby the driving of the chain, as indicated by arrows 49,will rotate the sprockets 35 in counterclockwise direction and rotatethe sprockets 43 in, clockwise direction.

' During the operation of the harvester over the ground, the position ofthe digger bit or blade 29 is determined by depth control means"consisting either of a roller 50a, shown in Fig. 13, or the wheels 59,shown in Figs. 1 and 3, which engage the bottoms of the furrows betweenthe potato hills or mounds, thesewheels being dis posed on the oppositesides of the forward ends of the digger bit 29. The wheels 50 aresupported by brackets 5| which project downwardly from the forward endsof side bars 52 forming part of a U -shaped frame 53. The side bars 52are pivotally connected to the digger frame 21 by pins spaced from therear ends of the side bars 52, andthe rear ends of the side bars areconnected by links 55 with the forward ends'of lever arms 55 keyedonthetransverse shaft 28. It will be perceived that as the lever arms 56 are'swung upwardly, the pullexerted through the links 55 will tend to swingthe forward ends of the side bars 52 downward with relation to the frontends of the digger bits 29, or, on the other hand, if the wheels 59 arein engagement with the ground, the upward swinging of the lever arms 56will pull the rear ends of the side bars 52 upward, thereby moving thepins I5 upward and thereby lifting the digger frame 21 so that thedigger bit 29 will be moved upwar relatively to the wheels 58. Theswinging of the lever arms 55 for the purposeof raising or loweringthewheels 55 with relation to the digger bits. 29 is accomplished throughswinging movement ofa control lever .51 x

which is fixed on the. shaft 28 and has at its lower end an internallythreaded sleeve 58-which receives the lower threaded end of a rod 59,theupper end of which has thrust bearings 50 engaging a block 6! turnablymounted on the lower end of a lever 62 which is swingable on a shaft 53.Rotation of the lever 51 so as to swing the lever arms 56 isaccomplished through a depth control hand wheel54 connected by a shaft55 and a flexible coupling 56 with the upper end of'therod .59. Ancperatonstanding on the forward partofthe vehicle chassis, may watch theoperation of the digger mechanism and may adjust the digger bits 29vertically with relation to the wheels 50 as required by operatingconditions encountered. When the wheels 50 are moved vertically, due todeviations in the level of the ground over'which they travel, the diggerbits 29 will move but little as compared to the vertical movement of thewheels due to the actlon of thelinkage connection between the side bars52 and the digger frame 21." Accordingly,

vertical movement'of the wheels 50, as'they ride over the ground, willnot cause a great change in the level to which the digger bits 29 havebeen adjusted. Tubular arms 5311 project forwardly from theframe member53 to support coulters 53c in positions to cut off laterally extendingportions of vines. i

The vine-removing device R comprises upper and lower rollers 51 and 58mounted respectively on shafts '69 and 10 on which sprockets 1t and 12are fixed. The lower roller BBisdisposed rearwardly of and parallel tothe shaft 31, around which the rear end of the conveyor 39 travels,

so that a space 13 is provided between the rear end [4 of the conveyorand the front face 15 of the lower roller 68. The upper roller 51"isdisposed above and forwardly of the lower roller 58 so that the lowerportion of the upperroller 51 lies above the space I3. V

The surfaces of the rollers 57 and are provided with projecting fingersor nubs 16 of flexible character. In the preferred practice of theinvention, the rollers 51 and'68 are surfaced with a layer of rubberhaving rubber fingers projecting therefrom, these fingers ,intermeshingas shown. The rollers are driven at relatively high speed as compared tothe travel of the conveyor 30. For example, these rollers 51 and 58 mayhave a surface speed of approximately 1250 feet per minute as comparedto the 275' feet'per minute travel of the conveyor 39. As the vines passfrom the rear end 74 of the conveyor 39, where it passes around thesprockets 35, they are engaged by the fingers 16 of the upper. roller;5'! and/or by the fingers 15 of the lower roller 63 so that such vineswill be drawn at high velocity rearwardly between the upper and lowerrollers 57 and 68, and will be jerked away from the potatoes to whichthey are attached. Some of these detached potatoes will drop directlydownwardly upon a lateral, grid conveyor TE, and other of the potatoes,may be drawn against the surfaces of the rollers 5'! and 58', fromwhence they will drop onto the conveyor 11. A feature of thevineremoving device R resides in the placing of the upper roller 51ahead of the lower roller so that potatoes which may be thrown againstthe lower forward portion of the upper roller 51 will be deflecteddownwardly through the space l9 'or down wardly andrearwardly againstthe front face "15 of the lower roller 88, from which the potatoes thendrop downwardly onto the transverseconveyor Tl. The conveyors 3i and I!comprise parallel bars 18 connected at their; ends by links 19.

The conveyor [1 travels over a pair of sprockets Manda pairof conerollers Ma. The bars 18 of the conveyors 3i! and I! providegrids onwhich the, potatoes are supporting and. carried, and have spacesthroughwhich debris, such as soil, small clods, etc.,,may fall to theground.

To drive therollers 51 and 68, respectively,' in clockwise andcounterclockwise directions, a chain loop BI is threaded, as shown inFigs. Band 9, over a sprocket 82 which is fixed on theshaft 31, thesprocket "l2 associated with the roller 58, and over. an idler' '84 todrive the roller 58 in counterclockwise direction. The chain 8| engagesa sprocket 84', which is fixed cna shaft 85b, Figs. 8 and 9, which'issupported by spaced bearings '84c,.the shaft 8th being thereby driven inclockwise direction. A sprocket 83 is fixed on the shaft 85b and drivesa chain loop- 83 which extends around a sprocket H, associated with theroller 8.1;and aroundian'idler 85, thereby :driv-ingr-rthie rollertIrinclockwise direction. The lower roller 68 maybe driven atagreater-surface velocity than-the-roller 61, therebyproviding ashearing :onfrictional action between the upper and lower rollers 51 and68 which will prevent vmes from becoming wound around these rollers. Thetrans 'verse shaft 69 is supported by -.bearings 62a on members 6% whichmay swing upwardly, thereby givingthe roller 8? a floating support'withrelation to the roller 68. The upper ends of the members 692) are swungfrom the ends of the shaft 841) by blocks 69c.

The transverse conveyor H has a shaft 35 on which the sprockets :80 arefixed, and this shaft 86. is driven from a sprockets! through atorquelimiting orsatety clutch 8B. The sprocket 81 is driven by achain39 from a shaftSB which eX- tends'to the front ortionof the chassis i twhere it isconnected by chain and sprocket means 9! with a jack shaft 92which is in-turn driven by chainand sprocket means 93 from the powerout" put shaft I6 of the engine 1 4.

From the transverse conveyor '5'! the potatoes are delivered to anelevator 94 which is mounted on the side of the chassis. This-elevatorcomprises a belt member 95 having spaced rubbercovered flights 96. Thebelt member 85 is of link type and runs around cone rollers 31, underguide sprockets 91a and 9122, over guide sprockets 9'50, and arounddrive sprockets 93 mounted on a transverse shaft 99 at the upperportionof the elevator 94, and driven in clockwise direction by meanswhich will be later described.

The elevator $4. delivers the potatoes to the upper end of a cleaningdevice C comprising an upper roll I!!!) and downwardly succeeding rollsIUI. The rolls I09 and it! are mounted on horizontal shafts IE2 whichare parallel and are disposed in a sloping plane. This sloping plane hasan-inclination .of approximately 35 degrees to horizontal and therollsIt!) and ItI are accordingly disposed in downwardly stepped relation asshown in Figure 7. The rolls IE9 and I OI have rubber-covered surfacesfrom which small nubs I03 project, these nubs acting to clean thesurfaces of the potatoes as they travel down the cleaning device C, andalso serving as means for carrying 01f debris, such as small portions ofvines, twigs, and dirt, outwardly between the rolls. The rolls IUIlandIllI are all rotated in such direction that the surfaces thereof engagedby the potatoes move in a general upward direction. As viewed in Figure7, these rolls rotate in counterclockwise direction and therefore as thepotatoes engage the rolls and tend to travel downward, they aregivenrolling action so that the .rubber nubs I63 are brought into engagementwith substantially the entire surfaces of the potatoes to perform aneffective cleaning action. If apotato strikes an upper part ofa roll Iin a mannerto be thrown into engagement with the next roll above, thesurface of the upper roll,

'moving outwardly from the space between it and the roll on which thepotato lies, will throw the potato forwardly. Also, each upwardlysucceeding roll has a greater peripheral velocity than the rollpreceding the same so that it is not possible for a-large potato to passthrough the spaces between the rolls. The only potatoes which may.be'engaged .by the periphery of the upwardly succeeding-roll which is;.travel-ing at ,a higher velocitythan theperiphery ofthe roll which-istending to move the potato toward the gap. Therefore, the potato will beimpelled or rolled away from the gap. Therolls- IOI are of the samediameter, and the upper roll I00 is of considerably larger diameter forthey purpose .of providing at the upper end of the cleaningdevice C aroller surface of considerable, vertical dimension to act asa stopagainst. further-movement of any potato which is thrown upwardly towardthe upperend of the cleaning device.

The shafts I82 supporting the.rollsl00.have thereon sprockets I24 whichare graduallydecreased in size from the lowermost shaft to the uppermostshaft of the group of shafts I132. For example, eachupwardly succeedingsprocket I84 may have one less tooth than its preceding sprocket IM. Achain 555 runs over these sprocketc 804 to act as an interconnecting anddriving means. The driving of all. of the shafts I02is accomplished bydriving one of them; for :example, the lowermost shaft indicated at I92is driven through a torque-limiting or safety clutch I06 from asprocket.Ii)? driven through a chainIflS from a drive sprocket I09 fixed on thelongitudinal shaft 99.

From the cleaning device C the potatoesaredelivered onto the forwardportion of a horizontal conveyor IIB supported in a framestructureIIImounted on the chassis and being connected thereto by posts 26, I I2,and Il3,.and other frame and bracing.menibersshown. The conveyor II 0 ispositioned so that its ,upper portion constitutes arearwardlytravelingtableopen or closed type, which carries the potatoesrearwardly on the harvester to delivery chutes iMand IIE 'leading tosack-holding devices -I l 6 and I I'Leachof which is adapted to hold apotato sack II8 as shown in Figural. The conveyor I I0 is dividedintolanes H9, I213, and I2! by dividing walls I22and I23. At the rearends of, the walls i22 and H3 hinges i2 3 connect thereto swinging guidewalls I25 which converge rearwardly and are connected by a link I26 towhich a shifting lever i2? is attached, the forward, portion of thisshifting lever holder I I7. During the filling ofjthis sacks thepreviously filled sack is removed from the holder IIS and a new sack isconnected thereto. When the sack carried by the sack holder IITisfilled. the operator lifts the forward end of the lever I2! fromengagement with a stop iiie and shifts it along the-bar I 28 to aposition beyond the other stop H29, thereby swinging the guide members25 into a position to direct potatoes into the chute I I4.

A platform Hi9 is extended along the sides and across the rear of thechassis I0 on which workers may stand in order to perform the operationsof inspecting, sorting; removing debris, and sacking the potatoes. Theside lanes I20 and HI, which are segregated from the main or centrallane I I8 by the guide Walls 522 and i23, may be selectively employed toreceive any objects which'the sorters are required to remove from thecentral lane I I9, such objects consisting of rocks, clods, or potatoesof designated size. Theseside lanes I20 and I2I lead rearwardly tochutes I3I and'I32, and gates I33 may be provided between themouths ofthe chutes I3I and I32. When these gates I33 are positioned so as toclose the mouths of the chutes I32, materials carried along by theconveyor IIB in the lanes I28 and I2I will be deflected outwardly by thelaterally deflected rear end por tions I3 l of the walls I22 and i23into the chutes I3I. When the gates 133 are swung-into diagonal positionwherein the swinging ends thereof .engage the walls I22 and E23, theywill deflect ob jects carried by'the conveyor I ii) in the lanes 12?;and I21 into the chutes I32.

The conveyor H8 runs over rollers I38 and I51 and the upper portionthereof betweenthe rollers i565 and I31" is supported bylongitudinalbatsI38. The lower or return portion 'or'thejccnveycrisupported by roller means I38. The'conveyor I it is operated by driving"the roller I88, this being accomplished through use of a sprocket Hillwhich is fixed on a shaft I81 which'projects-from the roller I36. Thissprocket I88 is driven by a chain I52 which engages a sprocket I83supported on the chassis It. The sprocket 1581s mounted on shaft l l ldriven by a geari iii which in turn is driven bya pinion 56 fixed on thejack shaft 82. The chain I52 runs over the top of the sprocket I58 andthen under a sprocket! which is fixed on the far end of a shaft I88. Thechain I52 is then extended over and around an idler sprocket I59 andfrom this sprocket i lt returns to the sprocket I53.

n the near end of the shaft MS a sprocket I58 is fixed, this sprocketI-Ed driving 'a'chain' I51 extendingv'overa sprocket I52 fixed on an endof the shaft 89 which supports sprockets 88 around which the upper endof thebelt element 950i the elevator 95' iscarriedQthe result being thatthe chain I52 drives 'both"the"'elevator 9 and the conveyor'II8. I Theinvention further provides means for quickly lifting the diggingmechanism at the will of the operator; whenever he preceives' that soilconditions or objects in the pathjo'f travel of the harvester requirethat the'digging mechanism be elevated either partly or fully. Thislifting mechanism is hydraulically actuated by hydraulic fluid underpressure from' a pump I53 driveriv by 'a'idriveconnection I54ifrom theengine 'IA; ,"The lever 62 is'fixe'd'on' the shaft 63, and from thislever 62 a 1ever'I55 extends forwardly. Also fixed 'oh'th'e Shanta thereis a lever 155a whiciris substantially aduplicate" of the lever -I 55."The for- Ward ends of the levers I55 and I55a are connected to theupper ends of adjustable lifting links I58, the lower ends of which arepivotally connected at I51 to the side portions of the digger frameZ'I.A hydraulic cylinder piston mechanism, or jack, I58 has its rearward endI55 swingab-ly connected to the chassis III and has its forward endconnected by pivot means I60 to the lower portion of the lever 62. Thehydraulic jack I58 is connected by piping I6I with a hydraulic controlvalve mechanism IE2 and a control lever I63 is provided for operation ofthe valve mechanism I52 whereby hydraulic fluid under pressure may bedirected through the piping I6I to the hydraulic jack I58 to accomplisha swinging of the lever 82 forwardly and to swing the levers I55 andI55'a upwardly. The movement of the lever 62 by the jack I58 will betransmitted by the block BI and thrust bearing means 60 through the rod59 to the levers 51, so as to swing the lever 56 upward. At the sametime the upward movement of the levers I55 and I55a will be transmittedthrough the links I56 to the frame 21 of the digger mechanism, theresult being that the digger'mechanism and the depth control wheels willbe simultaneously swung upwardly, the dis tance which these parts aremoved upwardly depending upon the'degree to which the jack I58 isexpanded. It will be perceived that when the links I56 aremoved upwardso as to lift the frame 21 of the digger mechanism and the pivot pin I51thereof which engage the sidemembers 52 of the depth control means, thelevers 56 will be swung upwardly so that the rear ends of the sidemembers 52 will be simultaneously raised at such rate with relation tothe upward movement of thepivot pins I5 I that the points of the diggerbits 29 will travel upward at a faster rate than the wheels 58. Asshown, by'th'e fragmentary view I3, a conca'verolleriillb is at timesused instead of the wheels 50 previously described. This roller 5% iscarried by a transverse, shaft I85 supported below the forward portionof the U-shaped member-53 -by brackets I85. This roller 50b serves thesame purpose as the wheels 58 and in addition theretorolls downthe'potato vines andbreaks up clod's'. This roller 5% is wide enough tocover the potato hill or ridge I81 and will flatten the vines I88. Inaddition to this, the roller will break up any. hard crust at I89 andbreak up heavy clods, thereby contributing'to the facility of separatingthe potatoes from the clods, or soil. As the flexible grid conveyor 30travels up the digger frame 21', it is given a shaking movement by aplurality of toothed cams which are rotatably supported in position toengagethe edges of the, portion of the grid conveyor 38, therebyintermittently raising and dropping the grid conveyor 38 in 'a'manner'toshake the load carrie'dthereon'a'nd therebycause clods and debris to'drop through the grid conveyor 38.

The front wheels I I of the device are mounted on an axle I65 whichswings ion a vertical post I88 under the front portion of the, chassislfl. The rear wheels I2 are supported by steering knuckles I81 which areconnected to the outer ends of bars I58 which slide into the. ends of astationary axle tube. I69 connected to the chassis Ill. The front endsof the levers ,I10 of the'steeringknuckles I81 are connected by bars "Ito the ends of a tubular transverse steering bar I12. Bolts I13-v andI14 are provided to.connect the members I68 with the tube I69 and toconnect the bars I1! with'the' transverse bar I12. The bars I68 may beshifted so as to change the spacing between the wheels I2, and spacedopenings I15 are provided in the "bars I68 through which the bolts I13may be passed in different adjustments of the bars I68 relatively to theaxle tube I69. When a Wheel I2 is shifted inwardly or outwardly, the barI11 associated therewith will be shifted in a like manner relatively tothe ends of the bar I12, and the bolts I14 will be repositioned inopenings I18 provided in the end portions of the bar I12. Anintermediate portion of the bar I12 is connected by means of a clamp I11to the transverse portion of a cable I18 which extends around pulleysI19, supported on the chassis I8, to hinged connections I mounted on aplate I8I which is connected to the vertical post I66 supporting theaxle I65 of the front wheels II. When the front wheels II are turned, byswinging the axle I65 around the axis defined by the posts I66, thecable I18 will be shifted and the shifting of the cable I18 will betransmitted through the clamp I11 to the transverse bar I12, whereby thewheels I2 will be swung on the knuckles I67 in a direction opposite thatto which the front wheels have been turned. The wheels II are of suchsize that they may swing entirely under the forward portion of thechassis I0, but after the cable I18 has been shifted so as to carry thelevers I of the steering knuckles I67 to the limit of their angulartravel, no further movement of the cable I18 will be caused by theswinging of a wheel II toward and into a position directly under theforward end of the chassis ID for the reason that when the axle I65 ofthe front wheels II is swung 45 degrees in either direction-fromtransverse position, one or the other of the pivotal connections I80will travel overv center and no more movement of the cable will bethereby produced. To accomplish this result, the pivotal connections I80for the front ends of the cable I18 are disposed on radial lines I82which are positioned at angles X of substantially 45-degrees from alongitudinal line I83 through the'steering axis defined by the post I86.Therefore, when a pivotal connection I80 movesforward through this angleX, it will pass over the center line I83.

I claim:

1. In a potato harvester, a mobile chassis, crop-digging means mountedon the chassis for gathering the'potatoes and vines, a conveyor mountedon the chassis and extending to a point adjacent said digging means soas to receive potatoes and vines therefrom, means on said chassis fordriving said conveyor so as to convey the potatoes and vines away fromsaid digging means, vine-engaging means mounted on the chassisimmediately abovesaid conveyor so as to engage vines thereon, means fordriving said vine-engaging means faster than said conveyor,vine-grasping means mounted on the chassis rearwardly of said conveyorand said vine-engaging means, there being a space between saidvine-grasping means and said conveyor, and means on said chassis fordriving said vinegrasping means so as to carry the vines away from thepotatoes while the latter fall downwardly through said space between theconveyor and vine-grasping means. I

. 2 The invention set forth in claim 1, further characterized by 'areceiver below said space to receive the potatoes. 7

3. The invention set forth in claim 1, further characterized by saidconveyor. comprising an endless element having an upper rearwardlymovable crop-conveying run, and said vine-engaging means including anendless element having vine-engaging fingers, and means supporting saidvine-engaging means on the chassis so that the fingers extendingdownwardly from the lower run of said vine-engaging means engage thevines on said crop-conveying uppe run of the conveyor.

4.'The invention set forth in claim 1, further characterized by saidvine-grasping means comprising a pair of rollers carried on the chassisrearwardly of said conveyor, one roller being spaced rearwardly-of saidconveyor and the other REFERENCES CITED The following references are ofrecord in the file of this patent:

UNITED STATES PATENTS Number Name Date 534,403 Mechwart Feb. 19, 1895796,017 Rose -1 Aug. 1, 1905 1,020,524 Todd Mar. 19, 1912 1,087,153 ToddFeb. 17, 1914 1,650,753 ,Jasperson Nov. 29, 1927 1,715,218 Wright May28,1929 1,789,527 Larinan Jan. 20,1931 1,800,622 Granberg Apr. 14, 19312,081,346 Altgelt May 25, 1937 2,114,263" Heaslet Apr. 12, 19382,209,282 Rodin July 23, 1940 2,215,516 Schooler Sept. 24, 19402,277,450 1 Parr Mar. 24, 1 942 2,318,194 Brown May 4, 1943 2,365,077Hertzler et a1 .Dec. 12, 1944 2,452,418 Zuckerman .Oct..26, 1948

